Thin display devices using liquid crystals or an organic EL phenomenon are being used. In particular, display devices using an organic EL phenomenon are different to those using liquid crystals since it is possible to display vivid images because they are light emitting. In addition, in recent years flexible display devices are being developed by using materials such as flexible substrates.
For example, it is possible to exemplify Japanese Laid Open Patent 2003-157970 as a technology related to a display device using an organic EL phenomenon. The display device disclosed in this document is provided with an organic EL device provided above a glass substrate, a sealing component adhered to the top of the glass substrate via an adhesive and covering the organic EL device, and an indicator which changes color by adsorbing moisture in regions apart from a display region above a glass substrate
In a display device which uses an organic EL phenomenon, it can not be said that an organic EL device includes sufficient resistance to moisture or oxygen. As a result, sealing structure is provided on a substrate when assembling a display device so that moisture or oxygen does not enter the interior from the exterior.
However, even when sealing is performed, it is difficult to completely prevent moisture from entering after manufacture of a display device which sometimes leads to a deterioration or damage to a display.
Therefore, the present invention proposes a display device which can detect the infiltration of moisture before deterioration or damage to a display occurs.